When you added custom links in table of database with language prefix that didn't create on website, you will have fatal error:
The website encountered an unexpected error. Please try again later.
Error: Call to a member function getName() on null in Drupal\xmlsitemap_custom\Controller\XmlSitemapCustomListController->render() (line 97 of modules/contrib/xmlsitemap/xmlsitemap_custom/src/Controller/XmlSitemapCustomListController.php).
Drupal\xmlsitemap_custom\Controller\XmlSitemapCustomListController->render()
call_user_func_array() (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 564)
Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 169)
Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 81)
Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 58)
Drupal\Core\StackMiddleware\Session->handle() (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass() (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 23)
Stack\StackedHttpKernel->handle() (Line: 709)
Drupal\Core\DrupalKernel->handle() (Line: 19)
Install xmlsitemap module and enable xmlsitemap_custom submdule
Add to table DB xmlsitemap row with values for custom link and language prefix that not available on website (column language) OR Add custom link to some language by UI and then remove language from Drupal (it stay added custom link in DB).
Try to open tab Custom links of XML Sitemap configuration by UI
Get fatal Error: Call to a member function getName() on null in Drupal\xmlsitemap_custom\Controller\XmlSitemapCustomListController->render() (line 97 of modules/contrib/xmlsitemap/xmlsitemap_custom/src/Controller/XmlSitemapCustomListController.php).
Add some check for existing languages in modules/contrib/xmlsitemap/xmlsitemap_custom/src/Controller/XmlSitemapCustomListController.php.
Needs review
1.5
Code
Hello.
I have added some additional condition and tab Custom links of XML Sitemap configuration by UI opens when in table of DB available links to not created languages.